Methamphetamine and HIV-1 Tat Synergistically Induce Microglial Pyroptosis Via Activation of the AIM2 Inflammasome.

Objective: Human immunodeficiency virus (HIV)-infected individuals who abuse methamphetamine (METH) exhibit more severe neurotoxicity and cognitive impairment. Pyroptosis, a programmed cell death pathway mediated by the inflammasome, has been implicated in various neurological diseases. This study aimed to elucidate the role of the AIM2 inflammasome in METH- and HIV-1 Tat-induced pyroptosis in human brain tissue and in vitro models.

Methods: Postmortem brain tissue from HIV-infected individuals with a history of METH abuse was analyzed for pyroptosis markers and AIM2 inflammasome components using immunohistochemistry, immunofluorescence, and Western blotting. BV2 microglial cells were lentivirally transduced to knockdown AIM2 expression. DNA damage was assessed using Western blotting and the comet assay. Expression of pyroptosis-related proteins was evaluated by electron microscopy, Western blotting, and immunofluorescence. Cell viability was measured using the CCK8 assay.

Results: Elevated levels of pyroptosis markers and AIM2 inflammasome components were observed in brain tissue from HIV-infected METH users. METH and Tat synergistically induced pyroptosis in BV2 cells in a time- and concentration-dependent manner, accompanied by DNA damage and activation of the AIM2 inflammasome. Knockdown of AIM2 significantly reduced the expression of pyroptosis-related proteins.

Conclusion: METH and HIV-1 Tat proteins synergistically induce microglial pyroptosis by activating the AIM2 inflammasome through dsDNA damage. These findings suggest that targeting the AIM2 inflammasome may be a promising therapeutic strategy for HIV-associated neurocognitive disorder (HAND).